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Silurus biwaensis (Tomoda, 1961)

Image contributors to this species:

Nakamura, M; Keys to the Freshwater Fishes of Japan Fully Illustrated in Colors (2) KENPEI (1) Ben Lee (1)

ScotCat Sources:

Other Sources:

Relevant Information:

One of three species of Silurus that are in Japan and is also the largest. The rock catfish, S. lithophilus, the Biwi catfish, S. biwaensis and the far eastern catfish S. asotus. Reproduction: Based on observations, a female first searches for a spawning site, with a male following behind. Immediately the female stops, the male first places his head under that of the female and then, by bending his body towards her anal fin, positions himself such that his tail is towards the end of the female's snout. From this position, the male then begins to wrap his tail around the head of the female, gradually winding his body tighter and moving along the body of the female until positioned at the center of her body. The male then winds his body tightly around the dorsal side of the female's abdomen for 20-30 seconds. The female then shakes her head from side to side several times, and orientates her body downward. This behavior causes the male to become separated from the female. Immediately after separation, the female releases a large number of eggs, and circles around with the male following on the inside. Although gamete release by the male was not actually observed, it seems likely that the eggs are fertilised during circling. After circling, the pair turns round twice violently, causing the eggs to become widely scattered. The pair then swim away with the female in the lead.

Common Name:

Eurasian catfish, Biwi catfish

Synonyms:

Parasilurus biwaensis

Family:

Siluridae

Distribution:

Asia: Endemic to Lake Biwa, Japan. Type locality: Offshore of Onoé, Lake Biwa-ko, Japan.

Size:

115.0cm. (3ft 10ins)

Temp:

10-20°C (47-67°F)

p.H.

6.0-8.0.

Reference:

Nakamura, M; Keys to the Freshwater Fishes of Japan Fully Illustrated in Colors. Hokuryukan, 1963.
Kobayakawa, M., 1989. Systematic revision of the catfish genus Silurus, with description of a new species from Thailand and Burma. Jap. J. Ichthyol. 36(2):155-186.
Ferraris, C.J. Jr., 2007. Checklist of catfishes, recent and fossil (Osteichthyes: Siluriformes), and catalogue of siluriform primary types. Zootaxa 1418:1-628.
Froese, R. and D. Pauly. Editors. 2021. FishBase. World Wide Web electronic publication. www.fishbase.org, ( 08/2021 ).

Family: Siluridae Back to Ident-A-Cat Click on Thumbnails

Silurus biwaensis

Silurus biwaensis
Head view

Silurus biwaensis

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